Rotary engines, such as for example Wankel engines, use the eccentric rotation of a piston to convert pressure into a rotating motion, instead of using reciprocating pistons. In these engines, the rotor includes a number of apex or seal portions which remain in contact with a peripheral wall of the rotor cavity of the engine throughout the rotational motion of the rotor to create a plurality of rotating chambers when the rotor rotates.
In a never-ending quest to achieve greater power output, Wankel engines have relatively low rotor recess volume in order to achieve the high volumetric expansion ratio required for such increased power output. However, such engines may not be fully optimized for use in turbocompounding systems, and thus room for improvement exists.